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ABSTRACTGenetic variation in heading dates is essential for developing a rational rice cultivation program, optimizing irrigation practices, and advancing plant breeding in year-round irrigated environments. In this study, we investigated the heading dates of eight rice varieties with varying degrees of photoperiod sensitivity under natural field conditions by conducting year-round periodic sowing in 2019 in Nay Pyi Taw, located in the central region of Myanmar. We elucidated genetic differences in critical day length by observing the longest day length at 30 days before heading, which is likely to be the starting point for floral induction. We analyzed two phenological models: the conventional developmental rate (DVR) model and a modified model considering the critical day length. These analyses aimed to uncover the genetic differences in phenological parameters: temperature sensitivity, photoperiod sensitivity, and earliness among rice varieties. Incorporating the critical day length into the DVR model significantly improved its accuracy in predicting heading dates, particularly for photoperiod-sensitive rice varieties. The parameters derived from the 2019 data proved effective for predicting heading dates in 2018, especially for photoperiod-sensitive varieties. The genetic variation in critical day length and model parameters could be valuable for adapting rice cultivars to different seasons and determining yield and agronomic practices for varietal development programs. These findings contribute to a deeper understanding of rice phenology and the genetic basis for photoperiod sensitivity in Myanmar rice.

Background: Several hypotheses regarding the pathomechanisms of schizophrenia have been proposed. If schizophrenia is a unitary disease, then these pathological processes must be linked; however, if such links do not exist, schizophrenia may best be considered a group of disorders. Only a few studies have examined the relationships among these pathomechanisms. Herein, we examined the relationships among deficient myelination, NMDA receptor hypofunction, and metabolic dysregulation by measuring various plasma markers and examining their correlations. Methods: Plasma samples were collected from 90 patients with schizophrenia and 68 healthy controls. Concentrations of nardilysin (N-arginine dibasic convertase, NRDC), a positive regulator of myelination, the NMDA receptor co-agonist d-serine and glycine, various additional amino acids related to NMDA receptor transmission (glutamate, glutamine, and l-serine), and homocysteine (Hcy), were measured. Concentrations were compared using independent samples t-test or logistic regression, and associations were evaluated using Pearson's correlation coefficients. Results: Plasma glycine (t = 2.05, p = 0.042), l-serine (t = 2.25, p = 0.027), and homocysteine (t = 3.71, p

Abstract Background Edwardsiella tarda (E. tarda) is a Gram-negative facultative anaerobe belonging to Enterobacteriales and is commonly isolated from fishes and reptiles. Infection due to E. tarda is uncommon among humans, with a reported human retention rate of 0.001%. It can cause sepsis in the elderly or those with pre-existing conditions such as liver failure, autoimmune disease, or malignancy. E. tarda is susceptible to many antibiotics; however, a high mortality rate (approximately 40%) has been reported with sepsis. Case presentation A 65-year-old woman presented to our hospital with a chief complaint of fever and abdominal pain for 2 days. Her blood tests showed elevated inflammatory markers, and contrast-enhanced computed tomography showed distention and wall thickening of the gallbladder and inflammation of peri-gallbladder fat. Subsequently, a diagnosis of cholecystitis with systemic inflammatory response syndrome was made. Laparoscopic cholecystectomy was performed after starting antimicrobial therapy. Blood culture of samples obtained on admission were positive for E. tarda, which was also detected in bile juice culture. Therefore, she was diagnosed with bacteremia caused by E. tarda, and postoperative antimicrobial therapy was continued. The patient improved, and there were no complications. Conclusions We experienced an extremely rare case of acute cholecystitis caused by E. tarda. Only a few cases of acute cholecystitis due to E. tarda have been reported. Furthermore, similar to this case, no previous study has reported the detection of E. tarda in both blood and bile cultures in acute cholecystitis cases. In addition to appropriate surgical intervention, continuous administration of antibiotics based on culture results resulted in a favorable outcome.

Abstract Background While several studies have revealed that neurodevelopmental disorders have a high probability of overlapping with substance use disorders, the effects of neurodevelopmental disorders on the courses of substance use disorders have hardly been examined. Methods This study targeted 637 alcohol-dependent individuals who received inpatient treatment and whose drinking situations were followed for 12 months after hospital discharge using mailed questionnaires. The comorbidity of psychiatric disorders and the characteristics associated with the neurodevelopmental disorders were assessed using several measurements at the time of hospital admission. The effects of neurodevelopmental disorders on the drinking courses of the subjects were then estimated. Results The presence of a current depressive episode or any anxiety disorder significantly lowered the abstinence rates during the follow-up period (p = 0.0195 and p = 0.0214, respectively). ADHD traits as assessed using the ADHD Self-report Scale (ASRS) predicted a significantly poorer abstinence rate (p = 0.0296). Similarly, attention-deficit characteristics assessed objectively through interviews predicted a significantly lower abstinence rate (p = 0.0346), and a sensitivity analysis enhanced these results (p = 0.0019). When the drinking patterns were classified into three groups, the subjects with attention-deficit characteristics had a significantly higher rate of “Recurrence” and lower rates of “Abstinence” and “Controlled drinking” (p = 0.013). In a multivariate proportional hazards analysis, the ASRS score was significantly correlated with the re-drinking risk (p = 0.003). Conclusion ADHD traits had significant effects on not only abstinence rates, but also on drinking pattern. The presence of ADHD traits, especially attention-deficit characteristics, influenced the drinking courses of alcohol-dependent individuals after hospital treatment.

Paw San Hmwe (PSH) is an indigenous rice variety from Myanmar with a good taste, a pleasant fragrance, and excellent elongation ability during cooking. However, its low yield potential and strong photoperiod sensitivity reduce its productivity, and it is vulnerable to climate changes during growth. To improve the photoperiod insensitivity, yield, and plant stature of PSH, the high-yield genes Grain number 1a (Gn1a) and Wealthy Farmer’s Panicle (WFP), together with the photoperiod insensitivity trait, were introgressed into PSH via marker-assisted backcross breeding and phenotype selection. For the photoperiod insensitivity trait, phenotypic selection was performed under long-day conditions during the dry season. After foreground selection of Gn1a and WFP via simple sequence repeat genotyping, genotyping-by-sequencing was conducted to validate the introgression of target genes and determine the recurrent parent genome recovery of the selected lines. The improved lines were insensitive to photoperiod, and the Gn1a and WFP introgression lines showed significantly higher numbers of primary panicle branches and spikelets per panicle than the recurrent parent, with comparative similarity in cooking and eating qualities. This study successfully improved PSH by decreasing its photoperiod sensitivity and introducing high-yield genes via marker-assisted selection. The developed lines can be used for crop rotation and double-season cropping of better-quality rice.

Abstract Background Foreign body ingestion is a common case in daily medical care, and it usually passes through the entire gastrointestinal tract naturally and is excreted in the feces. However, long and sharp foreign bodies may be difficult to pass naturally due to their shape. Here, we present a rare case of a duodenal foreign body, a toothbrush, that required laparoscopic surgical removal after a failed endoscopic attempt. Case presentation A 51-year-old male with intellectual disability presented to our hospital due to fever. Initially, he was diagnosed with aspiration pneumonia by chest X-ray and blood examination. However, abdominal X-ray examination suggested a foreign body, and a computed tomography scan revealed a toothbrush in the duodenum. Therefore, upper gastrointestinal endoscopy was immediately attempted to remove it, but it could not be safely removed because the handle part of the toothbrush seemed deeply embedded in the duodenal mucosa. Therefore, this case was diagnosed as duodenal incarceration of the toothbrush, and it was removed by laparoscopic surgery. The operation was performed safely, and the patient’s postoperative course was good without any complications. The extracted toothbrush was 15 cm in length. Conclusion We experienced a rare case of a duodenal foreign body, which was a toothbrush. The duodenal foreign body was safely removed by laparoscopic surgery for the first time.

BackgroundGrowing evidence suggests that intervention for smoking cessation enhances alcohol abstinence in treatment settings for alcohol dependence. However, research in this field is rare in Asians.MethodWe prospectively investigated the association of smoking status with drinking status using 9 surveys mailed during a 12-month period in 198 Japanese alcohol-dependent men (70 never/ex-smokers and 128 smokers) who admitted for the first time and completed a 3-month inpatient program for simultaneous alcohol abstinence and smoking cessation.ResultsNonsmoking during the first month after discharge and at the end of follow-up was reported in 28.9% and 25.0% of the baseline smokers, respectively. Kaplan-Meier estimates showed that a 12-month alcohol abstinence and heavy-drinking-free status were more frequent among never/ex-smokers (45.1% and 59.8%, respectively) and baseline smokers who quit smoking during the first month after discharge (59.0% and 60.8%, respectively), compared with sustained smokers (30.0% and 41.2%, respectively). Among the baseline smokers, the multivariate odds ratio (95% confidence interval) for smoking cessation during the first month were 2.77 (1.01-7.61) for alcohol abstinence during the period and 2.50 (1.00-6.25) for use of varenicline, a smoking cessation agent, during the inpatient program. After adjusting for age, drinking profile, lifestyle, family history of heavy or problem drinking, lifetime episodes of other major psychiatric disorders, and medications at discharge, the multivariate hazard ratios (HRs) for drinking lapse were 0.57 (0.37-0.89) for the never/ex-smoking and 0.41 (0.23-0.75) for new smoking cessation groups, respectively, compared with sustained smoking, while the corresponding HRs for heavy-drinking lapse were 0.55 (0.33-0.90) and 0.47 (0.25-0.88), respectively. The HR for drinking lapse was 0.63 (0.42-0.95) for the nonsmoking group (vs. smoking) during the observation period, while the HR for heavy-drinking lapse was 0.58 (0.37-0.91) for the nonsmoking group (vs. smoking) during the observation period. Other significant variables that worsened drinking outcomes were higher daily alcohol intake prior to hospitalization, family history of heavy or problem drinking and psychiatric medications at discharge.ConclusionNonsmoking was associated with better outcomes on the drinking status of Japanese alcohol-dependent men, and a smoking cessation program may be recommended to be integrated into alcohol abstinence programs.

Although immune checkpoint inhibitors (ICIs) can be used for lung cancer treatment, the activated immune response may cause immune-related adverse effects (irAEs). We present here a case of cytomegalovirus (CMV) enterocolitis during steroid therapy for an irAE. A 70-year-old man diagnosed with small-cell lung carcinoma (limited disease) received radiotherapy plus two chemotherapy cycles of cisplatin and etoposide. The tumor exhibited complete response but recurred after 3 years. After treatment with two cycles of carboplatin, etoposide, and atezolizumab, an inhibitors of programmed cell death receptor-1, he was switched to atezolizumab every 3 weeks for maintenance therapy. Diarrhea occurred after nine atezolizumab doses. With a strong suspicion of ICI-induced colitis, we administered methylprednisolone 500 mg for 3 days, followed by oral prednisolone 40 mg/day. Total colonoscopy during the treatment revealed mucosal inflammation of the total colon, suggesting immune-related colitis. Biopsies from the ulceration revealed crypt abscess with highly infiltrative plasma cells and lymphocytes. Furthermore, immunohistochemical staining showed positivity for CMV. With no improvement in watery diarrhea, the prednisolone dose was increased to 80 mg/day on the 11th day, and ganciclovir was additionally administered twice daily on the 26th day. On the 28th day, the patient had abdominal pain, and abdominal computed tomography revealed free air, resulting in the diagnosis of colon perforation. He underwent subtotal colectomy followed by ileostomy as emergency surgery. A colon specimen revealed colitis with CMV infection. We describe colon perforation in a patient with CMV enterocolitis complicated by refractory immune-related colitis.

Abstract Background Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is often caused by Helicobacter pylori and has a good prognosis. Rarely, patients with MALT lymphoma may have gastric cancer and have a poor prognosis. Case presentation We herein report a case in which surgical treatment was achieved for a 72-year-old male patient with gastric and duodenal MALT lymphoma coexisting multiple gastric cancers. He underwent upper endoscopy for epigastric discomfort, which revealed mucosal erosion on the posterior wall of the middle body of the stomach, an elevated lesion on the duodenal bulb, and a raised tumor on the antrum of the stomach. He was diagnosed with gastric and duodenal MALT lymphoma with early gastric cancer. One month after H. pylori eradication, a second upper endoscopy revealed no improvement in the gastric or duodenal mucosa, and areas of strong redness with a shallow recess just below the cardia of the stomach. As a result, a diagnosis of gastric and duodenal MALT lymphoma with two gastric cancers was made. Total gastrectomy with proximal duodenum resection using intraoperative upper endoscopy and regional lymph node dissection was performed. Pathologically, gastric and duodenal MALT lymphoma and three gastric cancers were detected. Since one of them was an advanced cancer, he started taking S-1 after his general condition improved. Conclusion For early detection of gastric and duodenal MALT lymphoma or gastric cancer, appropriate upper endoscopy and a biopsy are important. It is necessary to select a suitable treatment, such as H. pylori eradication, endoscopic treatment, surgery, chemotherapy, and irradiation, according to the disease state.

Study ObjectivesPeriocular skin warming before bedtime has been demonstrated to improve subjective sleep initiation in healthy adults with sleep difficulties scored six or higher in the Pittsburgh Sleep Questionnaire Index. This study aimed to investigate the effects of periocular skin warming on sleep initiation and thermoregulation processes in patients with insomnia disorder.MethodsParticipants included those with sleep difficulty (n = 22) and those with insomnia disorder (n = 16). Individuals from both groups were assessed at baseline (habitual sleep-wake schedule) and after two intervention conditions (use of a warming eye mask or a sham eye mask before habitual bedtime). The subjective and electroencephalographic sleep onset latency, along with proximal and distal skin temperature after periocular skin warming, were evaluated.ResultsPeriocular skin warming reduced objective sleep onset latency in independently of the group. Foot temperature and foot-proximal temperature gradient after getting into bed increased with periocular skin warming in independently of the group. However, the increase in hand temperature was observed only in the insomnia disorder group. Periocular skin warming also increased the normalized high frequency component of heart rate variability in independently of the group. The reduction of objective sleep onset latency was strongly associated with heat dissipation from the foot skin region.ConclusionThese results suggest that periocular skin warming promotes sleep initiation by enhancing heat dissipation from the distal skin regions in individuals with sleep difficulty and insomnia disorder. Periocular skin warming could thus be a novel non-pharmacological therapy for insomnia disorder.

Abstract Background Pseudosarcomatous myofibroblastic proliferation is a rare proliferative lesion of the submucosal stroma characterized by myofibroblast proliferation and inflammatory cell infiltration, and is mainly reported in the urinary system. Case presentation We report a 65-year-old male who was referred to our emergency room with right-side iliac fossa pain. The pain gradually worsened for approximately 2 months, and rebound tenderness was positive. Blood examination showed severe inflammatory findings, and enhanced computed tomography revealed a heterogeneous contrast-enhancing mass lesion measured to be 55 × 50 mm in size at the lower right abdomen. Based on these results, the patient was diagnosed with appendicitis with an abdominal abscess. As the inflammation was severe, we drained the abscess before performing surgery. Approximately 1 month after the abscess diminished, interval appendectomy was performed. Macroscopic findings of the resected specimen showed a perforated diverticulum of the appendix and a small adjacent nodule measured to be 14 mm in size. Histopathological examination with hematoxylin and eosin staining revealed that the nodule consisted of fibroblast proliferation and inflammatory cell infiltration. Furthermore, immunohistochemical examination showed positive for smooth muscle actin and desmin and negative for S-100, c-kit, and anaplastic lymphoma kinase. Based on these histopathological results, we diagnosed the nodule as an unusual case of a pseudosarcomatous myofibroblastic proliferation associated with perforation of the diverticulum of the appendix. Conclusion Herein, we report a rare case of a pseudosarcomatous myofibroblastic proliferation that occurred in the appendix with diverticulitis.

Abstract Background Pneumoperitoneum commonly occurs as a result of a viscus perforation and usually presents with peritoneal signs requiring emergent laparotomy. Spontaneous pneumoperitoneum is a rare condition characterized by intraperitoneal gas with no clear etiology. Case presentation We herein report a case in which conservative treatment was achieved for an 83-year-old male patient with spontaneous pneumoperitoneum that probably occurred due to duodenal diverticulosis. He had stable vital signs and slight epigastric discomfort without any other signs of peritonitis. A chest radiograph and computed tomography showed that a large amount of free gas extended into the upper abdominal cavity. Esophagogastroduodenoscopy showed duodenal diverticulosis but no perforation of the upper gastrointestinal tract. He was diagnosed with spontaneous pneumoperitoneum, and conservative treatment was selected. His medical course was uneventful, and pneumoperitoneum disappeared after 6 months. Conclusion In the management of spontaneous pneumoperitoneum, recognition of this rare condition and an accurate diagnosis based on symptoms and clinical imaging might contribute to reducing the performance of unnecessary laparotomy. However, in uncertain cases with peritoneal signs, spontaneous pneumoperitoneum is difficult to differentiate from free air resulting from gastrointestinal perforation and emergency exploratory laparotomy should be considered for these patients.

Gene duplication plays an important role in genetic diversification, adaptive evolution, and speciation. Understanding the mechanisms and effects of postzygotic isolation genes is important for further studies of speciation and crop breeding. The duplicate recessive genes hwe1 and hwe2 cause hybrid breakdown, characterized by poor vegetative growth and reproductive dysgenesis in intersubspecific crosses between Oryza sativa ssp. indica and japonica. Using a map-based cloning strategy, we found that HWE1 and HWE2 encode the Esa1-associated factor 6 (EAF6) protein, a component of histone acetyltransferase complexes. The indica hwe1 and japonica hwe2 alleles lacked functional EAF6, demonstrating that the double recessive homozygote causes hybrid breakdown. Morphological and physiological observations showed that weak plants with double recessive homozygotes had serious morphological defects with a wide range of effects on development and organs, leading to leaves with reduced chlorophyll content, flower and pistil malformation, and anomalies of gametogenesis. These findings suggest that EAF6 plays a pivotal role in the transcriptional regulation of essential genes during the vegetative and reproductive development of rice.

Abstract Background It is unclear whether the toe grip force (TGF) of the dominant foot (DF) and the lower limb function asymmetry (LLFA) in older adults are associated with fall risk. Therefore, this study aimed to investigate the effect of lower limb properties (such as TGF, muscle strength, and plantar sensation) on the risk of falls in older adults, while considering the foot dominance and asymmetry of lower limb function. Methods This study was a cross‐sectional study. We determined whether the lower limb function of the DF and non‐dominant foot (non‐DF) and LLFA had any effect on the fall risk in 54 older adults (mean ± standard deviation: 72.2 ± 6.0, range: 60–87 years). We examined the participants' fall history, Mini‐Mental State Examination (MMSE) score, lower limb function, and LLFA. To determine fall risk factors, we performed logistic regression analysis, with presence or absence of falls as the dependent variable. Results The independent variables were age, sex, MMSE score, two‐point discrimination of the heel (non‐DF) as plantar sensation index, and the TGF of both feet. Only the TGF of the DF was identified as a risk factor for falls (p

Postzygotic reproductive isolation maintains species integrity and uniformity and contributes to speciation by restricting the free gene flow between divergent species. In this study we identify causal genes of two Mendelian factors S22A and S22B on rice chromosome 2 inducing F1 pollen sterility in hybrids between Oryza sativa japonica-type cultivar Taichung 65 (T65) and a wild relative of rice species Oryza glumaepatula. The causal gene of S22B in T65 encodes a protein containing DUF1668 and gametophytically expressed in the anthers, designated S22B_j. The O. glumaepatula allele S22B-g, allelic to S22B_j, possesses three non-synonymous substitutions and a 2-bp deletion, leading to a frameshifted translation at the S22B C-terminal region. Transcription level of S22B-j and/or S22B_g did not solely determine the fertility of pollen grains by genotypes at S22B. Western blotting of S22B found that one major band with approximately 46 kDa appeared only at the mature stage and was reduced on semi-sterile heterozygotes at S22B, implying that the 46 kDa band may associated in hybrid sterility. In addition, causal genes of S22A in T65 were found to be S22A_j1 and S22A_j3 encoding DUF1668-containing protein. The allele of a wild rice species Oryza meridionalis Ng at S22B, designated S22B_m, is a loss-of-function allele probably due to large deletion of the gene lacking DUF1668 domain and evolved from the different lineage of O. glumaepatula. Phylogenetic analysis of DUF1668 suggested that many gene duplications occurred before the divergence of current crops in Poaceae, and loss-of-function mutations of DUF1668-containing genes represent the candidate causal genetic events contributing to hybrid incompatibilities. The duplicated DUF1668-domain gene may provide genetic potential to induce hybrid incompatibility by consequent mutations after divergence.

Reproductive barriers are commonly observed in both animals and plants, in which they maintain species integrity and contribute to speciation. This report shows that a combination of loss-of-function alleles at two duplicated loci, DUPLICATED GAMETOPHYTIC STERILITY 1 (DGS1) on chromosome 4 and DGS2 on chromosome 7, causes pollen sterility in hybrid progeny derived from an interspecific cross between cultivated rice, Oryza sativa, and an Asian annual wild rice, O. nivara. Male gametes carrying the DGS1 allele from O. nivara (DGS1-nivaras) and the DGS2 allele from O. sativa (DGS2-T65s) were sterile, but female gametes carrying the same genotype were fertile. We isolated the causal gene, which encodes a protein homologous to DNA-dependent RNA polymerase (RNAP) III subunit C4 (RPC4). RPC4 facilitates the transcription of 5S rRNAs and tRNAs. The loss-of-function alleles at DGS1-nivaras and DGS2-T65s were caused by weak or nonexpression of RPC4 and an absence of RPC4, respectively. Phylogenetic analysis demonstrated that gene duplication of RPC4 at DGS1 and DGS2 was a recent event that occurred after divergence of the ancestral population of Oryza from other Poaceae or during diversification of AA-genome species.

Abstract Delirium is a common and serious psychiatric syndrome caused by an underlying medical condition. It is associated with significant mortality and increased healthcare resource utilization. There are few biological markers of delirium, perhaps related to the etiologic heterogeneity of the syndrome. Functional near-infrared spectroscopy (fNIRS) is an optical topography system to measure changes in the concentration of oxygenated hemoglobin ([oxy-Hb]) in the cerebral cortex. We examined whether altered cortical brain activity in delirious patients with end stage liver disease (ESLD) is detected by fNIRS. We found that the [oxy-Hb] change during the verbal fluency task (VFT) was reduced in patients with ESLD compared with healthy controls (HC) in the prefrontal and bi-temporal regions. The [oxy-Hb] change during the sustained attention task (SAT) was elevated in patients with ESLD compared to HC in the prefrontal and left temporal regions. Notably, [oxy-Hb] change in the left dorsolateral prefrontal cortex during SAT showed a positive correlation with the severity of delirium. Our results suggest that [oxy-Hb] change in the prefrontal cortex during the sustained attention task measured with fNIRS might serve as a biological marker associated with delirium in ESLD patients.

Abstract Background High water use efficiency is essential to water-saving cropping. Morphological traits that affect photosynthetic water use efficiency are not well known. We examined whether leaf hairiness improves photosynthetic water use efficiency in rice. Results A chromosome segment introgression line (IL-hairy) of wild Oryza nivara (Acc. IRGC105715) with the genetic background of Oryza sativa cultivar ‘IR24’ had high leaf pubescence (hair). The leaf hairs developed along small vascular bundles. Linkage analysis in BC5F2 and F3 populations showed that the trait was governed by a single gene, designated BLANKET LEAF (BKL), on chromosome 6. IL-hairy plants had a warmer leaf surface in sunlight, probably due to increased boundary layer resistance. They had a lower transpiration rate under moderate and high light intensities, resulting in higher photosynthetic water use efficiency. Conclusion Introgression of BKL on chromosome 6 from O. nivara improved photosynthetic water use efficiency in the genetic background of IR24.

Music is commonly used to modify mood and has attracted attention as a potential therapeutic intervention. Despite the well-recognized effects of music on mood, changes in affective perception due to music remain majorly unknown. Here, we examined if the perception of aversive stimuli could be altered by mood-changing background music. Using subjective scoring data from 17 healthy volunteers, we assessed the effect of relaxing background music (RelaxBGM), busy background music (BusyBGM), or no background music (NoBGM) conditions on response to aversive white noise stimulation. Interestingly, affective response to the white noise was selectively alleviated, and white noise-related P3 component amplitude was reduced in BusyBGM. However, affective responses as well as P3 amplitude to reference pure tone stimuli were similar regardless of background music conditions. Interestingly, heart rate (HR) increased in BusyBGM, whereas no increase in HR was found in similar distress, NoBGM condition. These findings suggest that increase in HR, which happens during BusyBGM exposure, can be a reflecting feature of music that ameliorates the affective response to aversive stimuli, possibly through selective reduction in neurophysiological responses.

A genetic resource for studying genetic architecture of agronomic traits and environmental adaptation is essential for crop improvements. Here, we report the development of a rice nested association mapping population (aus-NAM) using 7 aus varieties as diversity donors and T65 as the common parent. Aus-NAM showed broad phenotypic variations. To test whether aus-NAM was useful for quantitative trait loci (QTL) mapping, known flowering genes (Ehd1, Hd1, and Ghd7) in rice were characterized using single-family QTL mapping, joint QTL mapping, and the methods based on genome-wide association study (GWAS). Ehd1 was detected in all the seven families and all the methods. On the other hand, Hd1 and Ghd7 were detected in some families, and joint QTL mapping and GWAS-based methods resulted in weaker and uncertain peaks. Overall, the high allelic variations in aus-NAM provide a valuable genetic resource for the rice community.

Wild rice species have long awns at their seed tips, but this trait has been lost through rice domestication. Awn loss mitigates harvest and seed storage; further, awnlessness increases the grain number and, subsequently, improves grain yield in Asian cultivated rice, highlighting the contribution of the loss of awn to modern rice agriculture. Therefore, identifying the genes regulating awn development would facilitate the elucidation of a part of the domestication process in rice and increase our understanding of the complex mechanism in awn morphogenesis. To identify the novel loci regulating awn development and understand the conservation of genes in other wild rice relatives belonging to the AA genome group, we analyzed the chromosome segment substitution lines (CSSL). In this study, we compared a number of CSSL sets derived by crossing wild rice species in the AA genome group with the cultivated species Oryza sativa ssp. japonica. Two loci on chromosomes 7 and 11 were newly discovered to be responsible for awn development. We also found wild relatives that were used as donor parents of the CSSLs carrying the functional alleles responsible for awn elongation, REGULATOR OF AWN ELONGATION 1 (RAE1) and RAE2. To understand the conserveness of RAE1 and RAE2 in wild rice relatives, we analyzed RAE1 and RAE2 sequences of 175 accessions among diverse AA genome species retrieved from the sequence read archive (SRA) database. Comparative sequence analysis demonstrated that most wild rice AA genome species maintained functional RAE1 and RAE2, whereas most Asian rice cultivars have lost either or both functions. In addition, some different loss-of-function alleles of RAE1 and RAE2 were found in Asian cultivated species. These findings suggest that different combinations of dysfunctional alleles of RAE1 and RAE2 were selected after the speciation of O. sativa, and that two-step loss of function in RAE1 and RAE2 contributed to awnlessness in Asian cultivated rice.

Pollen killer genes disable noncarrier pollens, and are responsible for male sterility and segregation distortion in hybrid populations of distantly related plant species. The genetic networks and the molecular mechanisms underlying the pollen killer system remain largely unknown. Two pollen killer genes, S24 and S35, have been found in an intersubspecific cross of Oryza sativa ssp. indica and japonica. The effect of S24 is counteracted by an unlinked locus EFS. Additionally, S35 has been proposed to interact with S24 to induce pollen sterility. These genetic interactions are suggestive of a single S24-centric genetic pathway (EFS–S24–S35) for the pollen killer system. To examine this hypothetical genetic pathway, the S35 and the S24 regions were further characterized and genetically dissected in this study. Our results indicated that S35 causes pollen sterility independently of both the EFS and S24 genes, but is dependent on a novel gene close to the S24 locus, named incentive for killing pollen (INK). We confirmed the phenotypic effect of the INK gene separately from the S24 gene, and identified the INK locus within an interval of less than 0.6 Mb on rice chromosome 5. This study characterized the genetic effect of the two independent genetic pathways of INK–S35 and EFS–S24 in indica–japonica hybrid progeny. Our results provide clear evidence that hybrid male sterility in rice is caused by several pollen killer networks with multiple factors positively and negatively regulating pollen killer genes.

The pigeon pea cyst nematode, Heterodera cajani, is an economically important plant-parasitic nematode in sesame production. The objective of the study was to investigate distribution of H. cajani in the major sesame producing areas in Myanmar. Before cultivation, soil samples were collected in 96 local farmer’s fields: (19 fields in Magway, 20 fields in Mandalay, 14 fields in Sagaing and 43 in Nay Pyi Taw), and nematode density was quantified by real-time PCR. The cyst nematode was detected in 63.2% of the fields in Magway and the mean density was 22.6 eggs equivalent (20 g soil)−1. In Mandalay and Nay Pyi Taw, the cyst nematode was detected in 40.0% and 18.6% of the fields with the mean densities of 9.9 and 21.0 eggs equivalent (20 g soil)−1, respectively. By contrast, the cyst nematode was not detected in Sagaing fields, in which sesame is rotated with paddy rice. Infestation of root-knot nematodes (RKN, Meloidogyne spp.) was also evaluated, because sesame is generally rotated with rice and pulses, which are attacked by RKN. The results showed 25.6% infestation of RKN with a mean density of 34.3 eggs equivalent (20 g soil)−1 only in Nay Pyi Taw, while there was no infestation in Magway, Mandalay, and Sagaing. The relationships between the nematode infestation level and the cropping patterns in each sesame growing area in Myanmar were discussed.

Abstract Objective To refine estimates of the burden of alcohol-related oesophageal cancer in Japan. Methods We searched PubMed for published reviews and original studies on alcohol intake, aldehyde dehydrogenase polymorphisms, and risk for oesophageal cancer in Japan, published before 2014. We conducted random-effects meta-analyses, including subgroup analyses by aldehyde dehydrogenase variants. We estimated deaths and loss of disability-adjusted life years (DALYs) from oesophageal cancer using exposure distributions for alcohol based on age, sex and relative risks per unit of exposure. Findings We identified 14 relevant studies. Three cohort studies and four case-control studies had dose-response data. Evidence from cohort studies showed that people who consumed the equivalent of 100 g/day of pure alcohol had an 11.71 fold, (95% confidence interval, CI: 2.67-51.32) risk of oesophageal cancer compared to those who never consumed alcohol. Evidence from case-control studies showed that the increase in risk was 33.11 fold (95% CI: 8.15-134.43) in the population at large. The difference by study design is explained by the 159 fold (95% CI: 27.2-938.2) risk among those with an inactive aldehyde dehydrogenase enzyme variant. Applying these dose-response estimates to the national profile of alcohol intake yielded 5279 oesophageal cancer deaths and 102 988 DALYs lost - almost double the estimates produced by the most recent global burden of disease exercise. Conclusion Use of global dose-response data results in an underestimate of the burden of disease from oesophageal cancer in Japan. Where possible, national burden of disease studies should use results from the population concerned.

Life histories and breeding systems strongly affect the genetic diversity of seed plants, but the genetic architectures that promote outcrossing in Oryza longistaminata, a perennial wild species in Africa, are not understood. We conducted a genetic analysis of the anther length of O. longistaminata accession W1508 using advanced backcross quantitative trait locus (QTL) analysis and chromosomal segment substitution lines (CSSLs) in the genetic background of O. sativa Taichung 65 (T65), with simple sequence repeat markers. QTL analysis of the BC3F1 population (n = 100) revealed that four main QTL regions on chromosomes 3, 5, and 6 were associated to anther length. We selected a minimum set of BC3F2 plants for the development of CSSLs to cover as much of the W1508 genome as possible. The additional minor QTLs were suggested in the regional QTL analysis, using 21 to 24 plants in each of the selected BC3F2 population. The main QTLs found on chromosomes 3, 5, and 6 were validated and designated qATL3, qATL5, qATL6.1, and qATL6.2, as novel QTLs identified in O. longistaminata in the mapping populations of 94, 88, 70, and 95 BC3F4 plants. qATL3, qATL5, and qATL6.1 likely contributed to anther length by cell elongation, whereas qATL6.2 likely contributed by cell multiplication. The QTLs were confirmed again in an evaluation of the W1508ILs. In several chromosome segment substitution lines without the four validated QTLs, the anthers were also longer than those of T65, suggesting that other QTLs also increase anther length in W1508. The cloning and diversity analyses of genes conferring anther length QTLs promotes utilization of the genetic resources of wild species, and the understanding of haplotype evolution on the differentiation of annuality and perenniality in the genus Oryza.

We investigated 321 varieties to identify the aleurone traits that are closely related to the lipid content of rice. Brown rice seeds were cut crosswise near the center with a razor blade and the cut surface was stained with Oil Red O, and then observed under integrated fluorescence microscope (BZ9000). We found wide variations among varieties in the area stained, but the japonica group contained many varieties with a large stained area. We selected 17 representative varieties covering the whole range of stained areas and confirmed the thickness of aleurone layer using Kawamoto’s film method (micro-thin sections that were created with cryomicrotome). Aleurone traits were examined under a light microscope and measured. We found a strong correlation between the area of the aleurone layer and the stained area (r = 0.799***) and between the thickness of the aleurone layer and the thickness of the stained region (r = 0.543*). The area of the stained region therefore provides a fast and effective indicator for selecting varieties for the thickness of the aleurone layer. We also measured the amount (mg per 100 seeds) and proportion of triacylglycerols (TAGs) to 1 g of seed (mg g-1) in brown rice seeds without embryos. The amount and proportion of TAG to 1 g of seed were both significantly correlated with the area, average thickness and percentage of aleurone layer. This suggests that the aleurone traits will be good indicators for the selection of varieties with high levels of TAG.

Using backcross inbred lines (BILs) derived from a cross between temperate japonica rice cultivars, Moritawase and Koshihikari, we validated the major quantitative trait loci (QTL) for eating quality and textural characteristics on chromosomes (Chr) 1, 2, 3, 6, 7, 10, and 12. Significant genetic differences in eating quality among BILs were detected at the QTL on Chr 3 and corresponded to the differences between the parents. Although differences in eating quality on the other chromosomes were not significant by t-test, cluster analysis and principal component analysis clearly showed that the genetic effects of the QTLs on Chr 6, 7, and 10 were similar to that on Chr 3, but the genetic effects of QTLs on Chr 1, 2, and 12 were entirely different from that on Chr 3. We previously identified that textural characteristics were highly correlated with eating quality. In this study, genetic differences in textural characteristics were similar to the genetic differences in eating quality among BILs. These results reveal major QTLs for eating quality of Koshihikari on Chr 3, 6, 7, and 10. The QTL on Chr 3 contributed most to the improvement of eating quality and textural characteristics.